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A meteorite lands on our Earth. It is made of a rigid, indestructible material (containing a payload). When the meteorite strikes, its kinetic energy will cause a blast of stones, dirt, heat, etc. Normal physical applies, except for its indestructibility.

It is about 1-2m diameter, smooth, and approximately round with a density and elasticity comparable to rock. Based on this chart it will have a KE of about 0.2kt on atmospheric entry.

Being indestructible, it will not airburst.

It arrives at, say, a 45 degree angle. It strikes a rocky mountain range, as opposed to, say, a desert.

What would happen to the meteorite in this scenario? Would it dig in deeper? Bounce?

How does its indestructibility affect the consequences to its environment, compared to a normal meteorite with the same KE on impact?

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    $\begingroup$ If the meteorite bounces or not will depend in large part on the properties of the meteorite itself and what it is made of. So we need to know more about this indestructible stuff to answer the question. $\endgroup$
    – Slarty
    Jun 27 '20 at 15:50
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    $\begingroup$ For any reasonable density of the meteorite, most of the kinetic energy will be dissipated in the atmosphere. The meterite will hit the ground with the terminal velocity of an object with the same shape and density, which we don't know since you have not told us its density. $\endgroup$
    – AlexP
    Jun 27 '20 at 17:29
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It's indestructible, but not unstoppable. Normal meteorites of this size bust in the upper atmosphere when the effects of heating and deceleration overcome their strength. Since that can't happen with this meteorite, the energy that would normally be expended doing it will end up as heat in the atmosphere. That won't add enough heat, as compared to a normal meteorite, to make any noticeable difference. It will come to a halt relative to Earth and then fall, hitting at its terminal velocity in Earth's atmosphere.

Since we know its size, the terminal velocity depends mainly on its mass, and secondarily on its surface smoothness. The velocity is unlikely to be much over 1Km/sec, so it won't make much of a crater, say 3-4 metres across, and isn't going fast enough to embed itself in rock. It will bounce, since it can't shatter, and since it lands in a mountain range, will probably roll downhill for a bit until it ends up in a low spot or snags on something.

If is is observed falling, anyone who reaches the fall site before weather obscures the marks of bounces and rolling will realise something odd is going on, and will be able to follow the trail.

The differences from a normal meteor of this mass is that it reaches the ground in one piece, with the effects above. A normal meteor will mostly be vaporised at altitude, although some grains and small pebbles might well reach the ground.

I hope the payload was well-padded, since it will have experienced some severe shocks.

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    $\begingroup$ I have on good authority that inside, there is indestructible bubble wrap. $\endgroup$
    – Willk
    Jun 27 '20 at 18:57
  • $\begingroup$ But where does the energy that would otherwise go towards bursting the meteoroid go? $\endgroup$
    – Daron
    Jun 27 '20 at 19:49
  • $\begingroup$ @Daron: Added that. It makes little difference. $\endgroup$ Jun 27 '20 at 21:00
  • $\begingroup$ @JohnDallman Don't big destrictible meteors usually burst really high up to begin with, and so most of the energy is already converted into heat in the atmosphere? $\endgroup$
    – Daron
    Jun 27 '20 at 21:26
  • $\begingroup$ @JohnDallman Oh I didn't see this meteor was itty bitty. $\endgroup$
    – Daron
    Jun 27 '20 at 21:28
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This page from American Meteor Society seems to indicate that your one meter diameter object would be retarded by the atmosphere and then after that it would reach a terminal velocity generally be somewhere between 0.1 and 0.2 km/sec (200 mph to 400 mph).

https://www.amsmeteors.org/fireballs/faqf/#:~:text=The%20meteorite%20then%20quickly%20reaches,deceleration%20due%20to%20atmospheric%20drag.

There is a crater calculator at

http://keith.aa.washington.edu/craterdata/scaling/index.htm

That seems to assume somewhat large objects and higher impact velocities, but it also points to a paper that discusses the calculator.

http://keith.aa.washington.edu/craterdata/scaling/index.htm

The paper seems to indicate that if you hit a hard object that you get spalling rather than a creator.

So like john Dallman's answer above, it may be (depending on the shape and terminal velocity of the object) a lot more like a fast plane crash into the mountain. I guess the height of the bounce would depend on the amount of energy lost in the collision, and deformation of the surrounding material.

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